Previously, many types of rescue tools have been used to provide an effective means to pry or cut open damaged vehicles at the scene of an accident. Further, other machine tools have been developed with similar operational characteristics.
A search of the prior art did not disclose any patents or industry literature that read directly on the claims of the instant invention. However, the following U.S. patents are considered related:
U.S. Pat. No.InventorIssue Date3,819,153Hurst et al.Jun. 25, 19744,333,330PorterJun. 8, 19824,392,263AmorosoJul. 12, 19834,734,983BrickApr. 5, 19885,301,533JacksonApr. 12, 19945,544,862HickersonAug. 13, 19965,622,353Painter et al.Apr. 22, 19975,956,992PattonSep. 28, 19996,244,568PattonJun. 12, 20017,107,812PattonSep. 19, 2006
Hurst in U.S. Pat. No. 3,819,153 teaches a portable rescue tool using fluid actuated force that is movable along the longitudinal axis of the base for positioning the arms to move the outer ends toward and way from each other to close and open.
U.S. Pat. No. 4,333,330 issued to Porter is for a spreader tool that has opposed force arms which are separated and pivoted while mounted on a base member. When separated and pivoted, the arms achieve annular movement in an opposite direction in response to axial movement of a driven piston of an associated jack. The inner edges of the arms rest upon rollers mounted on the forward end of the piston. A curve of the inner edge of the arms form an angle at which a constant axial force of the piston is applied to the arm by the roller such that the force is always constant.
Amoroso in U.S. Pat. No. 4,392,263 teaches a rescue tool including a body with a cylinder and an outward-extending piston. Jaw members are connected to the body with links and include outer prying portions, inner cutting portions and intermediate shearing portions. The tool may be powered by a bi-directional motor or directly from a wrecker motor vehicle system.
U.S. Pat. No. 4,734,983 issued to Brick teaches a cutting tool that is effective for cutting through sheet metal when extricating accident victims. The tool has one curved movable blade and one stationary blade. The stationary blade is formed on an anvil that is anchored within the frame of the tool and locked within the frame with a dowel.
U.S. Pat. No. 5,301,533 of Jackson discloses a machine tool that relates to manufacturing operations for gripping, clamping, piercing and hemming workpieces. Two pairs of arms are arranged in an opposed, inverted relationship with respect to each other and are pivotally connected at one end to the drive. Each arm has a cam formed therein. The cams in each of the pairs of arms are identically constructed in opposed inverted relationship. Cam followers, which are mounted on the linear drive member, engage the cams during movement to pivot the arms between the open and closed position. Each cam has an arcuate shape at an obtuse angle with respect to a pivot pin that connects each of the pairs of arms the drive.
U.S. Pat. No. 5,544,862 of Hickerson is for a spreading tool that is actuated by an electric motor. Torque at any position is achieved with selectable spreading or cutting motions using a rotary multiple stage speed-reducing gearbox, which is driven by a motor running on a 12 volt DC power supply.
Painter et al in U.S. Pat. No. 5,622,353 discloses a rescue tool having a pair of spreader arms with a pivot point therebetween. A pair of links attached to the arms are reciprocally moveable between retracted and extended positions along an axis of movement. A third pivotal coupling couples the spreader arm pivot point to the housing.
U.S. Pat. No. 5,956,992 issued to Patton, the instant inventor, is for a rescue tool consisting of a first arm that functions in combination with an interlocking second arm, which operates with a drive yoke. Another yoke includes a pair of cam pins that traverse a cam slot in each arm and a drive rod is connected to the drive yoke.
Patton's own U.S. Pat. No. 6,244,568 teaches a rescue spreading tool that provides a spreading, crushing or cutting motion. A stationary yoke is attached to a cylinder and a pair of spreader arms are attached to the cylinder and are free to rotate in opposed directions. A pusher cam yoke is formed integrally with the cylinder ram and engages the arms, thereby pushing them apart when the ram is extended. A pair of toggle links attached to the yoke continue to push the arms apart, thus creating a secondary thrust.
U.S. Pat. No. 7,107,812 also of Patton is for a hydraulic rescue tool utilizing a hydraulic cylinder with a yoke attached, with a handle for manipulating the tool. Rotation of the cylinder yoke prevents injury if the tool binds. Pivotal links connect the implement unit with quick release pins, thus making the implement unit easily removable. Two embodiments of the implement unit are taught, with a cutter unit for severing material and a spreader unit for prying apart structural elements when a vehicle is deformed to rescue a trapped victim.
For background purposes and as indicative of the art to which the invention is related, reference may be made to the remaining patents located in the patent search:
U.S. Pat. No.InventorIssue Date2,447,401Ferguson, et al.Aug. 17, 19483,570,835McPhersonMar. 16, 19714,886,635Forster, et al.Dec. 12, 19985,425,260GehronJun. 20, 1995